diff options
Diffstat (limited to 'drivers/mtd/nand/raw/omap_gpmc.c')
| -rw-r--r-- | drivers/mtd/nand/raw/omap_gpmc.c | 1037 |
1 files changed, 1037 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c new file mode 100644 index 0000000..6a05050 --- /dev/null +++ b/drivers/mtd/nand/raw/omap_gpmc.c @@ -0,0 +1,1037 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2004-2008 Texas Instruments, <www.ti.com> + * Rohit Choraria <rohitkc@ti.com> + */ + +#include <common.h> +#include <asm/io.h> +#include <linux/errno.h> +#include <asm/arch/mem.h> +#include <linux/mtd/omap_gpmc.h> +#include <linux/mtd/nand_ecc.h> +#include <linux/bch.h> +#include <linux/compiler.h> +#include <nand.h> +#include <linux/mtd/omap_elm.h> + +#define BADBLOCK_MARKER_LENGTH 2 +#define SECTOR_BYTES 512 +#define ECCCLEAR (0x1 << 8) +#define ECCRESULTREG1 (0x1 << 0) +/* 4 bit padding to make byte aligned, 56 = 52 + 4 */ +#define BCH4_BIT_PAD 4 + +#ifdef CONFIG_BCH +static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2, + 0x97, 0x79, 0xe5, 0x24, 0xb5}; +#endif +static uint8_t cs_next; +static __maybe_unused struct nand_ecclayout omap_ecclayout; + +#if defined(CONFIG_NAND_OMAP_GPMC_WSCFG) +static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE] = + { CONFIG_NAND_OMAP_GPMC_WSCFG }; +#else +/* wscfg is preset to zero since its a static variable */ +static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE]; +#endif + +/* + * Driver configurations + */ +struct omap_nand_info { + struct bch_control *control; + enum omap_ecc ecc_scheme; + uint8_t cs; + uint8_t ws; /* wait status pin (0,1) */ +}; + +/* We are wasting a bit of memory but al least we are safe */ +static struct omap_nand_info omap_nand_info[GPMC_MAX_CS]; + +/* + * omap_nand_hwcontrol - Set the address pointers corretly for the + * following address/data/command operation + */ +static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd, + uint32_t ctrl) +{ + register struct nand_chip *this = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(this); + int cs = info->cs; + + /* + * Point the IO_ADDR to DATA and ADDRESS registers instead + * of chip address + */ + switch (ctrl) { + case NAND_CTRL_CHANGE | NAND_CTRL_CLE: + this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd; + break; + case NAND_CTRL_CHANGE | NAND_CTRL_ALE: + this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_adr; + break; + case NAND_CTRL_CHANGE | NAND_NCE: + this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat; + break; + } + + if (cmd != NAND_CMD_NONE) + writeb(cmd, this->IO_ADDR_W); +} + +/* Check wait pin as dev ready indicator */ +static int omap_dev_ready(struct mtd_info *mtd) +{ + register struct nand_chip *this = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(this); + return gpmc_cfg->status & (1 << (8 + info->ws)); +} + +/* + * gen_true_ecc - This function will generate true ECC value, which + * can be used when correcting data read from NAND flash memory core + * + * @ecc_buf: buffer to store ecc code + * + * @return: re-formatted ECC value + */ +static uint32_t gen_true_ecc(uint8_t *ecc_buf) +{ + return ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) | + ((ecc_buf[2] & 0x0F) << 8); +} + +/* + * omap_correct_data - Compares the ecc read from nand spare area with ECC + * registers values and corrects one bit error if it has occurred + * Further details can be had from OMAP TRM and the following selected links: + * http://en.wikipedia.org/wiki/Hamming_code + * http://www.cs.utexas.edu/users/plaxton/c/337/05f/slides/ErrorCorrection-4.pdf + * + * @mtd: MTD device structure + * @dat: page data + * @read_ecc: ecc read from nand flash + * @calc_ecc: ecc read from ECC registers + * + * @return 0 if data is OK or corrected, else returns -1 + */ +static int __maybe_unused omap_correct_data(struct mtd_info *mtd, uint8_t *dat, + uint8_t *read_ecc, uint8_t *calc_ecc) +{ + uint32_t orig_ecc, new_ecc, res, hm; + uint16_t parity_bits, byte; + uint8_t bit; + + /* Regenerate the orginal ECC */ + orig_ecc = gen_true_ecc(read_ecc); + new_ecc = gen_true_ecc(calc_ecc); + /* Get the XOR of real ecc */ + res = orig_ecc ^ new_ecc; + if (res) { + /* Get the hamming width */ + hm = hweight32(res); + /* Single bit errors can be corrected! */ + if (hm == 12) { + /* Correctable data! */ + parity_bits = res >> 16; + bit = (parity_bits & 0x7); + byte = (parity_bits >> 3) & 0x1FF; + /* Flip the bit to correct */ + dat[byte] ^= (0x1 << bit); + } else if (hm == 1) { + printf("Error: Ecc is wrong\n"); + /* ECC itself is corrupted */ + return 2; + } else { + /* + * hm distance != parity pairs OR one, could mean 2 bit + * error OR potentially be on a blank page.. + * orig_ecc: contains spare area data from nand flash. + * new_ecc: generated ecc while reading data area. + * Note: if the ecc = 0, all data bits from which it was + * generated are 0xFF. + * The 3 byte(24 bits) ecc is generated per 512byte + * chunk of a page. If orig_ecc(from spare area) + * is 0xFF && new_ecc(computed now from data area)=0x0, + * this means that data area is 0xFF and spare area is + * 0xFF. A sure sign of a erased page! + */ + if ((orig_ecc == 0x0FFF0FFF) && (new_ecc == 0x00000000)) + return 0; + printf("Error: Bad compare! failed\n"); + /* detected 2 bit error */ + return -EBADMSG; + } + } + return 0; +} + +/* + * omap_enable_hwecc - configures GPMC as per ECC scheme before read/write + * @mtd: MTD device structure + * @mode: Read/Write mode + */ +__maybe_unused +static void omap_enable_hwecc(struct mtd_info *mtd, int32_t mode) +{ + struct nand_chip *nand = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(nand); + unsigned int dev_width = (nand->options & NAND_BUSWIDTH_16) ? 1 : 0; + unsigned int ecc_algo = 0; + unsigned int bch_type = 0; + unsigned int eccsize1 = 0x00, eccsize0 = 0x00, bch_wrapmode = 0x00; + u32 ecc_size_config_val = 0; + u32 ecc_config_val = 0; + int cs = info->cs; + + /* configure GPMC for specific ecc-scheme */ + switch (info->ecc_scheme) { + case OMAP_ECC_HAM1_CODE_SW: + return; + case OMAP_ECC_HAM1_CODE_HW: + ecc_algo = 0x0; + bch_type = 0x0; + bch_wrapmode = 0x00; + eccsize0 = 0xFF; + eccsize1 = 0xFF; + break; + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + case OMAP_ECC_BCH8_CODE_HW: + ecc_algo = 0x1; + bch_type = 0x1; + if (mode == NAND_ECC_WRITE) { + bch_wrapmode = 0x01; + eccsize0 = 0; /* extra bits in nibbles per sector */ + eccsize1 = 28; /* OOB bits in nibbles per sector */ + } else { + bch_wrapmode = 0x01; + eccsize0 = 26; /* ECC bits in nibbles per sector */ + eccsize1 = 2; /* non-ECC bits in nibbles per sector */ + } + break; + case OMAP_ECC_BCH16_CODE_HW: + ecc_algo = 0x1; + bch_type = 0x2; + if (mode == NAND_ECC_WRITE) { + bch_wrapmode = 0x01; + eccsize0 = 0; /* extra bits in nibbles per sector */ + eccsize1 = 52; /* OOB bits in nibbles per sector */ + } else { + bch_wrapmode = 0x01; + eccsize0 = 52; /* ECC bits in nibbles per sector */ + eccsize1 = 0; /* non-ECC bits in nibbles per sector */ + } + break; + default: + return; + } + /* Clear ecc and enable bits */ + writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control); + /* Configure ecc size for BCH */ + ecc_size_config_val = (eccsize1 << 22) | (eccsize0 << 12); + writel(ecc_size_config_val, &gpmc_cfg->ecc_size_config); + + /* Configure device details for BCH engine */ + ecc_config_val = ((ecc_algo << 16) | /* HAM1 | BCHx */ + (bch_type << 12) | /* BCH4/BCH8/BCH16 */ + (bch_wrapmode << 8) | /* wrap mode */ + (dev_width << 7) | /* bus width */ + (0x0 << 4) | /* number of sectors */ + (cs << 1) | /* ECC CS */ + (0x1)); /* enable ECC */ + writel(ecc_config_val, &gpmc_cfg->ecc_config); +} + +/* + * omap_calculate_ecc - Read ECC result + * @mtd: MTD structure + * @dat: unused + * @ecc_code: ecc_code buffer + * Using noninverted ECC can be considered ugly since writing a blank + * page ie. padding will clear the ECC bytes. This is no problem as + * long nobody is trying to write data on the seemingly unused page. + * Reading an erased page will produce an ECC mismatch between + * generated and read ECC bytes that has to be dealt with separately. + * E.g. if page is 0xFF (fresh erased), and if HW ECC engine within GPMC + * is used, the result of read will be 0x0 while the ECC offsets of the + * spare area will be 0xFF which will result in an ECC mismatch. + */ +static int omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat, + uint8_t *ecc_code) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(chip); + const uint32_t *ptr; + uint32_t val = 0; + int8_t i = 0, j; + + switch (info->ecc_scheme) { + case OMAP_ECC_HAM1_CODE_HW: + val = readl(&gpmc_cfg->ecc1_result); + ecc_code[0] = val & 0xFF; + ecc_code[1] = (val >> 16) & 0xFF; + ecc_code[2] = ((val >> 8) & 0x0F) | ((val >> 20) & 0xF0); + break; +#ifdef CONFIG_BCH + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: +#endif + case OMAP_ECC_BCH8_CODE_HW: + ptr = &gpmc_cfg->bch_result_0_3[0].bch_result_x[3]; + val = readl(ptr); + ecc_code[i++] = (val >> 0) & 0xFF; + ptr--; + for (j = 0; j < 3; j++) { + val = readl(ptr); + ecc_code[i++] = (val >> 24) & 0xFF; + ecc_code[i++] = (val >> 16) & 0xFF; + ecc_code[i++] = (val >> 8) & 0xFF; + ecc_code[i++] = (val >> 0) & 0xFF; + ptr--; + } + break; + case OMAP_ECC_BCH16_CODE_HW: + val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[2]); + ecc_code[i++] = (val >> 8) & 0xFF; + ecc_code[i++] = (val >> 0) & 0xFF; + val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[1]); + ecc_code[i++] = (val >> 24) & 0xFF; + ecc_code[i++] = (val >> 16) & 0xFF; + ecc_code[i++] = (val >> 8) & 0xFF; + ecc_code[i++] = (val >> 0) & 0xFF; + val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[0]); + ecc_code[i++] = (val >> 24) & 0xFF; + ecc_code[i++] = (val >> 16) & 0xFF; + ecc_code[i++] = (val >> 8) & 0xFF; + ecc_code[i++] = (val >> 0) & 0xFF; + for (j = 3; j >= 0; j--) { + val = readl(&gpmc_cfg->bch_result_0_3[0].bch_result_x[j] + ); + ecc_code[i++] = (val >> 24) & 0xFF; + ecc_code[i++] = (val >> 16) & 0xFF; + ecc_code[i++] = (val >> 8) & 0xFF; + ecc_code[i++] = (val >> 0) & 0xFF; + } + break; + default: + return -EINVAL; + } + /* ECC scheme specific syndrome customizations */ + switch (info->ecc_scheme) { + case OMAP_ECC_HAM1_CODE_HW: + break; +#ifdef CONFIG_BCH + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + + for (i = 0; i < chip->ecc.bytes; i++) + *(ecc_code + i) = *(ecc_code + i) ^ + bch8_polynomial[i]; + break; +#endif + case OMAP_ECC_BCH8_CODE_HW: + ecc_code[chip->ecc.bytes - 1] = 0x00; + break; + case OMAP_ECC_BCH16_CODE_HW: + break; + default: + return -EINVAL; + } + return 0; +} + +#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH + +#define PREFETCH_CONFIG1_CS_SHIFT 24 +#define PREFETCH_FIFOTHRESHOLD_MAX 0x40 +#define PREFETCH_FIFOTHRESHOLD(val) ((val) << 8) +#define PREFETCH_STATUS_COUNT(val) (val & 0x00003fff) +#define PREFETCH_STATUS_FIFO_CNT(val) ((val >> 24) & 0x7F) +#define ENABLE_PREFETCH (1 << 7) + +/** + * omap_prefetch_enable - configures and starts prefetch transfer + * @fifo_th: fifo threshold to be used for read/ write + * @count: number of bytes to be transferred + * @is_write: prefetch read(0) or write post(1) mode + * @cs: chip select to use + */ +static int omap_prefetch_enable(int fifo_th, unsigned int count, int is_write, int cs) +{ + uint32_t val; + + if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX) + return -EINVAL; + + if (readl(&gpmc_cfg->prefetch_control)) + return -EBUSY; + + /* Set the amount of bytes to be prefetched */ + writel(count, &gpmc_cfg->prefetch_config2); + + val = (cs << PREFETCH_CONFIG1_CS_SHIFT) | (is_write & 1) | + PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH; + writel(val, &gpmc_cfg->prefetch_config1); + + /* Start the prefetch engine */ + writel(1, &gpmc_cfg->prefetch_control); + + return 0; +} + +/** + * omap_prefetch_reset - disables and stops the prefetch engine + */ +static void omap_prefetch_reset(void) +{ + writel(0, &gpmc_cfg->prefetch_control); + writel(0, &gpmc_cfg->prefetch_config1); +} + +static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int len) +{ + int ret; + uint32_t cnt; + struct omap_nand_info *info = nand_get_controller_data(chip); + + ret = omap_prefetch_enable(PREFETCH_FIFOTHRESHOLD_MAX, len, 0, info->cs); + if (ret < 0) + return ret; + + do { + int i; + + cnt = readl(&gpmc_cfg->prefetch_status); + cnt = PREFETCH_STATUS_FIFO_CNT(cnt); + + for (i = 0; i < cnt / 4; i++) { + *buf++ = readl(CONFIG_SYS_NAND_BASE); + len -= 4; + } + } while (len); + + omap_prefetch_reset(); + + return 0; +} + +static inline void omap_nand_read(struct mtd_info *mtd, uint8_t *buf, int len) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + + if (chip->options & NAND_BUSWIDTH_16) + nand_read_buf16(mtd, buf, len); + else + nand_read_buf(mtd, buf, len); +} + +static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len) +{ + int ret; + uint32_t head, tail; + struct nand_chip *chip = mtd_to_nand(mtd); + + /* + * If the destination buffer is unaligned, start with reading + * the overlap byte-wise. + */ + head = ((uint32_t) buf) % 4; + if (head) { + omap_nand_read(mtd, buf, head); + buf += head; + len -= head; + } + + /* + * Only transfer multiples of 4 bytes in a pre-fetched fashion. + * If there's a residue, care for it byte-wise afterwards. + */ + tail = len % 4; + + ret = __read_prefetch_aligned(chip, (uint32_t *)buf, len - tail); + if (ret < 0) { + /* fallback in case the prefetch engine is busy */ + omap_nand_read(mtd, buf, len); + } else if (tail) { + buf += len - tail; + omap_nand_read(mtd, buf, tail); + } +} +#endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */ + +#ifdef CONFIG_NAND_OMAP_ELM +/* + * omap_reverse_list - re-orders list elements in reverse order [internal] + * @list: pointer to start of list + * @length: length of list +*/ +static void omap_reverse_list(u8 *list, unsigned int length) +{ + unsigned int i, j; + unsigned int half_length = length / 2; + u8 tmp; + for (i = 0, j = length - 1; i < half_length; i++, j--) { + tmp = list[i]; + list[i] = list[j]; + list[j] = tmp; + } +} + +/* + * omap_correct_data_bch - Compares the ecc read from nand spare area + * with ECC registers values and corrects one bit error if it has occurred + * + * @mtd: MTD device structure + * @dat: page data + * @read_ecc: ecc read from nand flash (ignored) + * @calc_ecc: ecc read from ECC registers + * + * @return 0 if data is OK or corrected, else returns -1 + */ +static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat, + uint8_t *read_ecc, uint8_t *calc_ecc) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(chip); + struct nand_ecc_ctrl *ecc = &chip->ecc; + uint32_t error_count = 0, error_max; + uint32_t error_loc[ELM_MAX_ERROR_COUNT]; + enum bch_level bch_type; + uint32_t i, ecc_flag = 0; + uint8_t count; + uint32_t byte_pos, bit_pos; + int err = 0; + + /* check calculated ecc */ + for (i = 0; i < ecc->bytes && !ecc_flag; i++) { + if (calc_ecc[i] != 0x00) + ecc_flag = 1; + } + if (!ecc_flag) + return 0; + + /* check for whether its a erased-page */ + ecc_flag = 0; + for (i = 0; i < ecc->bytes && !ecc_flag; i++) { + if (read_ecc[i] != 0xff) + ecc_flag = 1; + } + if (!ecc_flag) + return 0; + + /* + * while reading ECC result we read it in big endian. + * Hence while loading to ELM we have rotate to get the right endian. + */ + switch (info->ecc_scheme) { + case OMAP_ECC_BCH8_CODE_HW: + bch_type = BCH_8_BIT; + omap_reverse_list(calc_ecc, ecc->bytes - 1); + break; + case OMAP_ECC_BCH16_CODE_HW: + bch_type = BCH_16_BIT; + omap_reverse_list(calc_ecc, ecc->bytes); + break; + default: + return -EINVAL; + } + /* use elm module to check for errors */ + elm_config(bch_type); + err = elm_check_error(calc_ecc, bch_type, &error_count, error_loc); + if (err) + return err; + + /* correct bch error */ + for (count = 0; count < error_count; count++) { + switch (info->ecc_scheme) { + case OMAP_ECC_BCH8_CODE_HW: + /* 14th byte in ECC is reserved to match ROM layout */ + error_max = SECTOR_BYTES + (ecc->bytes - 1); + break; + case OMAP_ECC_BCH16_CODE_HW: + error_max = SECTOR_BYTES + ecc->bytes; + break; + default: + return -EINVAL; + } + byte_pos = error_max - (error_loc[count] / 8) - 1; + bit_pos = error_loc[count] % 8; + if (byte_pos < SECTOR_BYTES) { + dat[byte_pos] ^= 1 << bit_pos; + debug("nand: bit-flip corrected @data=%d\n", byte_pos); + } else if (byte_pos < error_max) { + read_ecc[byte_pos - SECTOR_BYTES] ^= 1 << bit_pos; + debug("nand: bit-flip corrected @oob=%d\n", byte_pos - + SECTOR_BYTES); + } else { + err = -EBADMSG; + printf("nand: error: invalid bit-flip location\n"); + } + } + return (err) ? err : error_count; +} + +/** + * omap_read_page_bch - hardware ecc based page read function + * @mtd: mtd info structure + * @chip: nand chip info structure + * @buf: buffer to store read data + * @oob_required: caller expects OOB data read to chip->oob_poi + * @page: page number to read + * + */ +static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip, + uint8_t *buf, int oob_required, int page) +{ + int i, eccsize = chip->ecc.size; + int eccbytes = chip->ecc.bytes; + int eccsteps = chip->ecc.steps; + uint8_t *p = buf; + uint8_t *ecc_calc = chip->buffers->ecccalc; + uint8_t *ecc_code = chip->buffers->ecccode; + uint32_t *eccpos = chip->ecc.layout->eccpos; + uint8_t *oob = chip->oob_poi; + uint32_t data_pos; + uint32_t oob_pos; + + data_pos = 0; + /* oob area start */ + oob_pos = (eccsize * eccsteps) + chip->ecc.layout->eccpos[0]; + oob += chip->ecc.layout->eccpos[0]; + + for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize, + oob += eccbytes) { + chip->ecc.hwctl(mtd, NAND_ECC_READ); + /* read data */ + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_pos, -1); + chip->read_buf(mtd, p, eccsize); + + /* read respective ecc from oob area */ + chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1); + chip->read_buf(mtd, oob, eccbytes); + /* read syndrome */ + chip->ecc.calculate(mtd, p, &ecc_calc[i]); + + data_pos += eccsize; + oob_pos += eccbytes; + } + + for (i = 0; i < chip->ecc.total; i++) + ecc_code[i] = chip->oob_poi[eccpos[i]]; + + eccsteps = chip->ecc.steps; + p = buf; + + for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) { + int stat; + + stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]); + if (stat < 0) + mtd->ecc_stats.failed++; + else + mtd->ecc_stats.corrected += stat; + } + return 0; +} +#endif /* CONFIG_NAND_OMAP_ELM */ + +/* + * OMAP3 BCH8 support (with BCH library) + */ +#ifdef CONFIG_BCH +/** + * omap_correct_data_bch_sw - Decode received data and correct errors + * @mtd: MTD device structure + * @data: page data + * @read_ecc: ecc read from nand flash + * @calc_ecc: ecc read from HW ECC registers + */ +static int omap_correct_data_bch_sw(struct mtd_info *mtd, u_char *data, + u_char *read_ecc, u_char *calc_ecc) +{ + int i, count; + /* cannot correct more than 8 errors */ + unsigned int errloc[8]; + struct nand_chip *chip = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(chip); + + count = decode_bch(info->control, NULL, SECTOR_BYTES, + read_ecc, calc_ecc, NULL, errloc); + if (count > 0) { + /* correct errors */ + for (i = 0; i < count; i++) { + /* correct data only, not ecc bytes */ + if (errloc[i] < SECTOR_BYTES << 3) + data[errloc[i] >> 3] ^= 1 << (errloc[i] & 7); + debug("corrected bitflip %u\n", errloc[i]); +#ifdef DEBUG + puts("read_ecc: "); + /* + * BCH8 have 13 bytes of ECC; BCH4 needs adoption + * here! + */ + for (i = 0; i < 13; i++) + printf("%02x ", read_ecc[i]); + puts("\n"); + puts("calc_ecc: "); + for (i = 0; i < 13; i++) + printf("%02x ", calc_ecc[i]); + puts("\n"); +#endif + } + } else if (count < 0) { + puts("ecc unrecoverable error\n"); + } + return count; +} + +/** + * omap_free_bch - Release BCH ecc resources + * @mtd: MTD device structure + */ +static void __maybe_unused omap_free_bch(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd_to_nand(mtd); + struct omap_nand_info *info = nand_get_controller_data(chip); + + if (info->control) { + free_bch(info->control); + info->control = NULL; + } +} +#endif /* CONFIG_BCH */ + +/** + * omap_select_ecc_scheme - configures driver for particular ecc-scheme + * @nand: NAND chip device structure + * @ecc_scheme: ecc scheme to configure + * @pagesize: number of main-area bytes per page of NAND device + * @oobsize: number of OOB/spare bytes per page of NAND device + */ +static int omap_select_ecc_scheme(struct nand_chip *nand, + enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) { + struct omap_nand_info *info = nand_get_controller_data(nand); + struct nand_ecclayout *ecclayout = &omap_ecclayout; + int eccsteps = pagesize / SECTOR_BYTES; + int i; + + switch (ecc_scheme) { + case OMAP_ECC_HAM1_CODE_SW: + debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n"); + /* For this ecc-scheme, ecc.bytes, ecc.layout, ... are + * initialized in nand_scan_tail(), so just set ecc.mode */ + info->control = NULL; + nand->ecc.mode = NAND_ECC_SOFT; + nand->ecc.layout = NULL; + nand->ecc.size = 0; + break; + + case OMAP_ECC_HAM1_CODE_HW: + debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (3 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + info->control = NULL; + /* populate ecc specific fields */ + memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl)); + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 1; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 3; + nand->ecc.hwctl = omap_enable_hwecc; + nand->ecc.correct = omap_correct_data; + nand->ecc.calculate = omap_calculate_ecc; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + for (i = 0; i < ecclayout->eccbytes; i++) { + if (nand->options & NAND_BUSWIDTH_16) + ecclayout->eccpos[i] = i + 2; + else + ecclayout->eccpos[i] = i + 1; + } + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + break; + + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: +#ifdef CONFIG_BCH + debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (13 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + /* check if BCH S/W library can be used for error detection */ + info->control = init_bch(13, 8, 0x201b); + if (!info->control) { + printf("nand: error: could not init_bch()\n"); + return -ENODEV; + } + /* populate ecc specific fields */ + memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl)); + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 8; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 13; + nand->ecc.hwctl = omap_enable_hwecc; + nand->ecc.correct = omap_correct_data_bch_sw; + nand->ecc.calculate = omap_calculate_ecc; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH; + for (i = 1; i < ecclayout->eccbytes; i++) { + if (i % nand->ecc.bytes) + ecclayout->eccpos[i] = + ecclayout->eccpos[i - 1] + 1; + else + ecclayout->eccpos[i] = + ecclayout->eccpos[i - 1] + 2; + } + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + break; +#else + printf("nand: error: CONFIG_BCH required for ECC\n"); + return -EINVAL; +#endif + + case OMAP_ECC_BCH8_CODE_HW: +#ifdef CONFIG_NAND_OMAP_ELM + debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (14 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + /* intialize ELM for ECC error detection */ + elm_init(); + info->control = NULL; + /* populate ecc specific fields */ + memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl)); + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.strength = 8; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 14; + nand->ecc.hwctl = omap_enable_hwecc; + nand->ecc.correct = omap_correct_data_bch; + nand->ecc.calculate = omap_calculate_ecc; + nand->ecc.read_page = omap_read_page_bch; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + for (i = 0; i < ecclayout->eccbytes; i++) + ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes - + BADBLOCK_MARKER_LENGTH; + break; +#else + printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n"); + return -EINVAL; +#endif + + case OMAP_ECC_BCH16_CODE_HW: +#ifdef CONFIG_NAND_OMAP_ELM + debug("nand: using OMAP_ECC_BCH16_CODE_HW\n"); + /* check ecc-scheme requirements before updating ecc info */ + if ((26 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) { + printf("nand: error: insufficient OOB: require=%d\n", ( + (26 * eccsteps) + BADBLOCK_MARKER_LENGTH)); + return -EINVAL; + } + /* intialize ELM for ECC error detection */ + elm_init(); + /* populate ecc specific fields */ + nand->ecc.mode = NAND_ECC_HW; + nand->ecc.size = SECTOR_BYTES; + nand->ecc.bytes = 26; + nand->ecc.strength = 16; + nand->ecc.hwctl = omap_enable_hwecc; + nand->ecc.correct = omap_correct_data_bch; + nand->ecc.calculate = omap_calculate_ecc; + nand->ecc.read_page = omap_read_page_bch; + /* define ecc-layout */ + ecclayout->eccbytes = nand->ecc.bytes * eccsteps; + for (i = 0; i < ecclayout->eccbytes; i++) + ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH; + ecclayout->oobfree[0].length = oobsize - nand->ecc.bytes - + BADBLOCK_MARKER_LENGTH; + break; +#else + printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n"); + return -EINVAL; +#endif + default: + debug("nand: error: ecc scheme not enabled or supported\n"); + return -EINVAL; + } + + /* nand_scan_tail() sets ham1 sw ecc; hw ecc layout is set by driver */ + if (ecc_scheme != OMAP_ECC_HAM1_CODE_SW) + nand->ecc.layout = ecclayout; + + info->ecc_scheme = ecc_scheme; + return 0; +} + +#ifndef CONFIG_SPL_BUILD +/* + * omap_nand_switch_ecc - switch the ECC operation between different engines + * (h/w and s/w) and different algorithms (hamming and BCHx) + * + * @hardware - true if one of the HW engines should be used + * @eccstrength - the number of bits that could be corrected + * (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16) + */ +int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength) +{ + struct nand_chip *nand; + struct mtd_info *mtd = get_nand_dev_by_index(nand_curr_device); + int err = 0; + + if (!mtd) { + printf("nand: error: no NAND devices found\n"); + return -ENODEV; + } + + nand = mtd_to_nand(mtd); + nand->options |= NAND_OWN_BUFFERS; + nand->options &= ~NAND_SUBPAGE_READ; + /* Setup the ecc configurations again */ + if (hardware) { + if (eccstrength == 1) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_HAM1_CODE_HW, + mtd->writesize, mtd->oobsize); + } else if (eccstrength == 8) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_BCH8_CODE_HW, + mtd->writesize, mtd->oobsize); + } else if (eccstrength == 16) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_BCH16_CODE_HW, + mtd->writesize, mtd->oobsize); + } else { + printf("nand: error: unsupported ECC scheme\n"); + return -EINVAL; + } + } else { + if (eccstrength == 1) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_HAM1_CODE_SW, + mtd->writesize, mtd->oobsize); + } else if (eccstrength == 8) { + err = omap_select_ecc_scheme(nand, + OMAP_ECC_BCH8_CODE_HW_DETECTION_SW, + mtd->writesize, mtd->oobsize); + } else { + printf("nand: error: unsupported ECC scheme\n"); + return -EINVAL; + } + } + + /* Update NAND handling after ECC mode switch */ + if (!err) + err = nand_scan_tail(mtd); + return err; +} +#endif /* CONFIG_SPL_BUILD */ + +/* + * Board-specific NAND initialization. The following members of the + * argument are board-specific: + * - IO_ADDR_R: address to read the 8 I/O lines of the flash device + * - IO_ADDR_W: address to write the 8 I/O lines of the flash device + * - cmd_ctrl: hardwarespecific function for accesing control-lines + * - waitfunc: hardwarespecific function for accesing device ready/busy line + * - ecc.hwctl: function to enable (reset) hardware ecc generator + * - ecc.mode: mode of ecc, see defines + * - chip_delay: chip dependent delay for transfering data from array to + * read regs (tR) + * - options: various chip options. They can partly be set to inform + * nand_scan about special functionality. See the defines for further + * explanation + */ +int board_nand_init(struct nand_chip *nand) +{ + int32_t gpmc_config = 0; + int cs = cs_next++; + int err = 0; + /* + * xloader/Uboot's gpmc configuration would have configured GPMC for + * nand type of memory. The following logic scans and latches on to the + * first CS with NAND type memory. + * TBD: need to make this logic generic to handle multiple CS NAND + * devices. + */ + while (cs < GPMC_MAX_CS) { + /* Check if NAND type is set */ + if ((readl(&gpmc_cfg->cs[cs].config1) & 0xC00) == 0x800) { + /* Found it!! */ + break; + } + cs++; + } + if (cs >= GPMC_MAX_CS) { + printf("nand: error: Unable to find NAND settings in " + "GPMC Configuration - quitting\n"); + return -ENODEV; + } + + gpmc_config = readl(&gpmc_cfg->config); + /* Disable Write protect */ + gpmc_config |= 0x10; + writel(gpmc_config, &gpmc_cfg->config); + + nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat; + nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd; + omap_nand_info[cs].control = NULL; + omap_nand_info[cs].cs = cs; + omap_nand_info[cs].ws = wscfg[cs]; + nand_set_controller_data(nand, &omap_nand_info[cs]); + nand->cmd_ctrl = omap_nand_hwcontrol; + nand->options |= NAND_NO_PADDING | NAND_CACHEPRG; + nand->chip_delay = 100; + nand->ecc.layout = &omap_ecclayout; + + /* configure driver and controller based on NAND device bus-width */ + gpmc_config = readl(&gpmc_cfg->cs[cs].config1); +#if defined(CONFIG_SYS_NAND_BUSWIDTH_16BIT) + nand->options |= NAND_BUSWIDTH_16; + writel(gpmc_config | (0x1 << 12), &gpmc_cfg->cs[cs].config1); +#else + nand->options &= ~NAND_BUSWIDTH_16; + writel(gpmc_config & ~(0x1 << 12), &gpmc_cfg->cs[cs].config1); +#endif + /* select ECC scheme */ +#if defined(CONFIG_NAND_OMAP_ECCSCHEME) + err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME, + CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE); +#else + /* pagesize and oobsize are not required to configure sw ecc-scheme */ + err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW, + 0, 0); +#endif + if (err) + return err; + +#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH + nand->read_buf = omap_nand_read_prefetch; +#else + if (nand->options & NAND_BUSWIDTH_16) + nand->read_buf = nand_read_buf16; + else + nand->read_buf = nand_read_buf; +#endif + + nand->dev_ready = omap_dev_ready; + + return 0; +} |